Incidence of tuberculosis and immunological profile of TB/HIV co-infected patients in Nigeria.

Background: We obtained estimates of the incidence of tuberculosis (TB) among patients receiving HIV Treatment. We also modeled the relationship between incident TB and change in CD4 count over the follow-up period.

Methods: We analyzed the incidence of TB over 10 years from initiation of HIV treatment among 345 HIV treatment-naïve persons, who were enrolled in a cohort in Kano, Nigeria. We used Generalized Estimating Equation [GEE] to identify determinants of TB incidence and model the relationship between the occurrences of TB with change in CD4 count over the follow-up period. We created Kaplan-Meier curves stratified by anti-retroviral therapy (ART) treatment failure status to examine the effect of first line ART treatment failure on occurrence of TB.

Result: During the 10-year period, 47(13.62%) had TB [incidence was 7.43 per (1,000) person year)]. It is associated with decreasing age (OR = 0.98), female gender (OR = 0.83), being on first line ART other than AZT (OR = 0.87), poor adherence (OR = 1.25), change in ART regimen (OR = 2.3) and ART treatment failure (OR = 1.51). Odds of TB occurrence was also associated with CD4 increment at 10 years (OR = 0.99). Those with TB/HIV co-infection tend to have statistically significant shorter time to failing first line ART regimen compared to those with HIV infection alone.

Conclusion: There was high incidence of TB in the studied HIV cohort with a deleterious effect on the outcome of ART treatment. There is need for early TB screening and re-screening among all HIV patients.